Improvement in the manufacture of gun-cotton



` J. J. R-'VY. MANUPAGTURB 'OP GUNGOTTON.

Patented Sept. 19, 1865.

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TH: Nonals mais co. womumo., wAmNnfnN. n. c.

UNITED STA-Tirs PATENT OFFICE.

J. J. RVY, OF

NO. 28 GROSVENOR STREET, EATON SQUARE, COUNTY OF MIDDLESEX, ENGLAND.

lIMPROVEMENT IN THE MANUFACTURE OF GUNfCOTTON.

Specification forming part of Letters Patent No. 50,083, dated September 19, 1865.

vention and in what matter the same is to be' performed to be particularlydescribed and ascertained in and by the `followingstatement thereoff-that'is to say y In the specication of a former paten t, grant' ed to me in 1862, there is described a process for manufacturing explosive compounds. This yprocess produces explosive compounds of more uniform quality than had theretofore been produced, but the process described is costly, usinga' great' deal of? acid, 'and tneresuts'arc not so uniform as I have since been able to obtain. f c

The object of my present invention is, then, to obtain more uniform results than can be obtained by working accordin g to the speciticap tion of the said former patent, and also greatly to reduce the cost of the process. place, in preparing the cotton find that if it Y. beonly Washed in water and dried, as heretofore, perfectly-uniform results are not obtained,

for the cotton as it comes from the spinning or twist-ing process is frequently greasy, and the grease is not removed by merely washing 'in Water. 'i therefore first wash the cottonf in. a Weak solution of potash or other alkalisay 30 Baumeand then complete the Washing with Water, as before.

In the converting process l proceed asfolf.

lows: steep the prepared cotton yarn, tuoroughly dried and in the vform of bundles ci.' lightly-twisted yarn, in an-acid mixture, using the apparatus represented in Figures 1, 2, 3.,

use, by preference, one part, by Weight, of nitric acid, specific gravity 1.485, and 4three parts, by weight,oi' sulphnric acid, specific gravity 1.84,

the acids being pure and thoroughly mixed together conveniently,as described in the speci- :iication of thepatent before referred to.

The apparatus consists of two cast-iron tanks, T T,- theinner tank, Tf, being kept cool-during the process In the firstby a constant ilow of cold water,

E, which is maintained through the outer vessel. The Water enters at m and leaves at n. This is done because the temperature in the dipping-tank should never rise above 800 Fahrenheit, and it should not fall below 400 Fahrenheit. y

The inner tank, T ,is divided into three compartlnents., E contains the store of acid mixture; F,the acid mixture in which the process of dipping or steeping is performed, and'G G represent the compartment `with the pot to receive the steeped cot-ton. Two or other convenient number of skeins of cotton yarn, together of about three to four ounces in weight, thoroughly desiccated, or containingno trace of moisture, are immersed at one operation-in the acid mixture contained in F. An ironspatula being used -to effect complete saturation of th'e cotton with the acids, this'will be effected in 'abontcnenrinnta Tnecottnn'risrnext removed from the bath, laid upon the perforated shelf i, and by means of a spatula pressed tov such au extent that the amount of mixed acid left ab-V Y Y sorbed by the cotton may be in the ratio of about one weightof cotton to ten and one-half Weightof acid mixture. This a practiced workman does as nearly as his judgment admits. The cotton Vskeins are next placed in the pot Gr, which is filled by repeated operations, and after each dipping the portion of acid absorbed is made good by taking acid from the compartment E and put-ting it into the compartment F. This is done by means ot' a spoon capable of containing just the measure of acid which should be used at each dipping operation. In this manner the surface of the acid in F should be always maintained at the same level, o p.

The pots Gr shouldbe of the .best earthenware.

the cotton is left exposed for about fortyeight hours. During this space-ot' time the pots Gr are covered and are kept cool. They are -for tated'water.

with gun-cotton.

this purpose immersed in a trough of water, through which a constant iiow is maintained. The temperature in the pots should be kept Within the limits above given for the dippingvessel.

It', notwithstanding the precautions, a pot should heat and commence to fume, as will hap-l pen if water gets into the pot, or it' the dripping be improperly conducted, the pot is removed and its contents rejected. `Considerable precaution is necessary to prevent the cotton reabsorbiu g moisture after it has beendried and before dripping, as a very shortexposure is suflicient to allow the cotton to absorb enough moisture to render it. unsuitable for use.

When the cotton is removed from the pots in which it was exposed for aboutforty-eigbthours to the action of the-acid mixture it is'pl'aced inacentrifngal machine, the drum of which regv -volves at a high speed-say a thirty-inch diameter drum revolving at about twelve hun# dred revolutions lper minuteto vthrowfoutmost of the waste acid soakedupby thecot;

ton. The contents of about six'pots are treated thus in one operation. When'the gun-cotton is removed from the centrifugalmachine each hank or skein separately is thrown into a tub under a moderate fall of ,water, and greatcare is taken that each hank or skein of gun-cotton is placed rapidly and at onceunder thefa'llingA water, and fully immersedfi'n the mnchlagihaving been thus placed into the water, the

gun-cotton skeins are left in, it for about ten'. minutes. After this lapseof time the skeins of gun-cotton are removed from the tub fron under the falling watenand directly placed.

i-nto another centrifugal machine similar tothat used forthe waste-acid operation, and, -the drum bein g m ade to revolve at a high speed ,them'uchdiluted acid is thrown out from the gun-cotton skeins. After this operation ordinary test-pa per will hardlyindicate any traces of acid; butthis operation should be `performed a second and even a third time, thesk'eins of gun-cotton being again placed into a similar tub'contain ing much-agitated water, and again returned to the centrifugal machine, to be freed from most. of the Wat-er. Thus every trace of 1ingering acid is effectuallyremoved from the exterior of the gun-cotton fibers. After this operation the gun-cotton skeins are placed into tanks which contain a series of trays.. These trays have perforated bottoms and tit the sides of the tanks. The lowesttray being filled with' insures the removal of acid traces from the iu-v ".up aroundv thel interior lof The contents of-labo'uti six pots until ultimately,

nearly dry,

hung up on rods in an open drying-shed: The strength of water-glass solution which I eniploy is about 12o Baume, and the temperature terior of the gun-cotton fibers. The gun-cotton.

skeins are washed in these tanks for at' least two days, but one week is preferable.

The water used for should yhe iltered.A

. When the gun-cotton is removed from'- these 'l tanks it is treatedin the man ner described in my former specification, before referred to,un til arriving'at the process of vsaturating with soluble'l glass.

Artificial ventilation is found togbe neces- "sary'ove'rthe V dippingtro'ugh, and also over:

vthe centrifugal machine, for separatin g the acid fromzthe cotton after it comes out of the pots Gr. -In order to effect the impregnation of gun'- cotton with soluble orv water glass I employ a centrifugal machine. l The gauze-drum is lined 'witha cloth and the skeins ot cotton'thoronghly saturated with water-glass form, as it were, a circular wall within it--say three or'four inches thick-then an inner cylinder or frame is dropped into the drum tokeep the skeins in theirplaces, and the drum is then filled with water-glass solution'. Thev drum is now rotated comparatively slov'vl'y; lso

Aas to keep up a steady dow through the cotton',v

`the drum being, however, 'stantly admitting more solution. the work goes on for two or three minutes,

In this wayl 'when the admission of Water-glass solution is stopped and the speed of the'drum is increased with a' thirtyeinch drum, a speed of twelve hundred revolutions per min; nte 'is obtained. The cotton, which is then is taken out and theskeins'are s hould'be about S20 Fahrenheit.

- The.water-glass-'solution may be used sev.

eral times, solongas itremainsclear.v It should be protected from the air.

' The cotton remains in the drying-sheds for several days, and by exposure to the atmosphere carbonic acid combines with the soda of' the water-glass, and the silica is precipitated upon the gun-cotton ber. lIfhe carbonate of soda'is got rid `ofafterward by careful and "continued washing in running water.

Thus it will be observed that inthe process the water-glass is applied in a nearly-cold state, l

for I have found that when itis used in a boiling state, as heretofore, less uniform results are obtained.

The nal cleansing of the cotton from any `dirt it' may have contracted in the process is ei'ected with soap and water. rinsed and dried in the air. is warmed in bad weather. Having thus described the natureof my said invention and the manner of performing the Afterward it is The drying-house same, I would have it understood that what .I

claim is-- 1.` The preparing the cotton for use in the the washing operations l should be. clear and pure, and if it cannot be easily obtained at once in suchy condition it solution, are built the drum, so as tol kept full by conalkaline solution.,

manufacture of guncotton by washing itinan 2. The process of dipping or steeping the cotton asvhereinbefore set forth, small and regularquantities of the cotton being dipped vone after the other in a dipping-vessel containing a zonsiderable quantity of acid, the con- Y tents of which are after-each operation brought back to the proper strength by the'eddition ot' fresh acid to compensate for'that removed'by the portion 'of cotton last dipped.

g 3. The general arrangement .of the apparal tu-hereinbefore described and shown inthe annexed drawings.

i 4. The separatin g' the acid from the ext rior i ofthe gun-cotton ber by saturating the cotton with Water and then again extracting this water .by means'ot'l a centrifugal machine, also the i separation of th'e acid from the interior of the gun-cotton fiber by arranging the cotton in layers on suitableperforated shelves and causing 

